sbin/routed/main.c

   1 /*
   2  * Copyright (c) 1983, 1988, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. Neither the name of the University nor the names of its contributors
  14  *    may be used to endorse or promote products derived from this software
  15  *    without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  *
  29  * @(#)main.c   8.1 (Berkeley) 6/5/93
  30  * $FreeBSD: src/sbin/routed/main.c,v 1.11.2.1 2000/08/14 17:00:03 sheldonh Exp $
  31  */
  32
  33 #include "defs.h"
  34 #include "pathnames.h"
  35 #include <signal.h>
  36 #include <fcntl.h>
  37 #include <sys/file.h>
  38
  39 pid_t   mypid;
  40
  41 naddr   myaddr;                         /* system address */
  42 char    myname[MAXHOSTNAMELEN+1];
  43
  44 int     verbose;
  45
  46 int     supplier;                       /* supply or broadcast updates */
  47 int     supplier_set;
  48 int     ipforwarding = 1;               /* kernel forwarding on */
  49
  50 int     default_gateway;                /* 1=advertise default */
  51 int     background = 1;
  52 int     ridhosts;                       /* 1=reduce host routes */
  53 int     mhome;                          /* 1=want multi-homed host route */
  54 int     advertise_mhome;                /* 1=must continue advertising it */
  55 int     auth_ok = 1;                    /* 1=ignore auth if we do not care */
  56
  57 struct timeval epoch;                   /* when started */
  58 struct timeval clk, prev_clk;
  59 static int usec_fudge;
  60 struct timeval now;                     /* current idea of time */
  61 time_t  now_stale;
  62 time_t  now_expire;
  63 time_t  now_garbage;
  64
  65 struct timeval next_bcast;              /* next general broadcast */
  66 struct timeval no_flash = {             /* inhibit flash update */
  67         EPOCH+SUPPLY_INTERVAL, 0
  68 };
  69
  70 struct timeval flush_kern_timer;
  71
  72 fd_set  fdbits;
  73 int     sock_max;
  74 int     rip_sock = -1;                  /* RIP socket */
  75 struct interface *rip_sock_mcast;       /* current multicast interface */
  76 int     rt_sock;                        /* routing socket */
  77 int     rt_sock_seqno;
  78
  79
  80 static  int get_rip_sock(naddr, int);
  81 static void timevalsub(struct timeval *, struct timeval *, struct timeval *);
  82
  83 int
  84 main(int argc,
  85      char *argv[])
  86 {
  87         int n, mib[4], off;
  88         size_t len;
  89         char *p, *q;
  90         const char *cp;
  91         struct timeval wtime, t2;
  92         time_t dt;
  93         fd_set ibits;
  94         naddr p_net, p_mask;
  95         struct interface *ifp;
  96         struct parm parm;
  97         char *tracename = 0;
  98
  99
 100         /* Some shells are badly broken and send SIGHUP to backgrounded
 101          * processes.
 102          */
 103         signal(SIGHUP, SIG_IGN);
 104
 105         openlog("routed", LOG_PID, LOG_DAEMON);
 106         ftrace = stdout;
 107
 108         gettimeofday(&clk, 0);
 109         prev_clk = clk;
 110         epoch = clk;
 111         epoch.tv_sec -= EPOCH;
 112         now.tv_sec = EPOCH;
 113         now_stale = EPOCH - STALE_TIME;
 114         now_expire = EPOCH - EXPIRE_TIME;
 115         now_garbage = EPOCH - GARBAGE_TIME;
 116         wtime.tv_sec = 0;
 117
 118         gethostname(myname, sizeof(myname)-1);
 119         gethost(myname, &myaddr);
 120
 121         while ((n = getopt(argc, argv, "sqdghmpAtvT:F:P:")) != -1) {
 122                 switch (n) {
 123                 case 's':
 124                         supplier = 1;
 125                         supplier_set = 1;
 126                         break;
 127
 128                 case 'q':
 129                         supplier = 0;
 130                         supplier_set = 1;
 131                         break;
 132
 133                 case 'd':
 134                         background = 0;
 135                         break;
 136
 137                 case 'g':
 138                         memset(&parm, 0, sizeof(parm));
 139                         parm.parm_d_metric = 1;
 140                         cp = check_parms(&parm);
 141                         if (cp != 0)
 142                                 msglog("bad -g: %s", cp);
 143                         else
 144                                 default_gateway = 1;
 145                         break;
 146
 147                 case 'h':               /* suppress extra host routes */
 148                         ridhosts = 1;
 149                         break;
 150
 151                 case 'm':               /* advertise host route */
 152                         mhome = 1;      /* on multi-homed hosts */
 153                         break;
 154
 155                 case 'A':
 156                         /* Ignore authentication if we do not care.
 157                          * Crazy as it is, that is what RFC 1723 requires.
 158                          */
 159                         auth_ok = 0;
 160                         break;
 161
 162                 case 't':
 163                         new_tracelevel++;
 164                         break;
 165
 166                 case 'T':
 167                         tracename = optarg;
 168                         break;
 169
 170                 case 'F':               /* minimal routes for SLIP */
 171                         n = FAKE_METRIC;
 172                         p = strchr(optarg,',');
 173                         if (p && *p != '\0') {
 174                                 n = (int)strtoul(p+1, &q, 0);
 175                                 if (*q == '\0'
 176                                     && n <= HOPCNT_INFINITY-1
 177                                     && n >= 1)
 178                                         *p = '\0';
 179                         }
 180                         if (!getnet(optarg, &p_net, &p_mask)) {
 181                                 msglog("bad network; \"-F %s\"",
 182                                        optarg);
 183                                 break;
 184                         }
 185                         memset(&parm, 0, sizeof(parm));
 186                         parm.parm_net = p_net;
 187                         parm.parm_mask = p_mask;
 188                         parm.parm_d_metric = n;
 189                         cp = check_parms(&parm);
 190                         if (cp != 0)
 191                                 msglog("bad -F: %s", cp);
 192                         break;
 193
 194                 case 'P':
 195                         /* handle arbitrary parameters.
 196                          */
 197                         q = strdup(optarg);
 198                         cp = parse_parms(q, 0);
 199                         if (cp != 0)
 200                                 msglog("%s in \"-P %s\"", cp, optarg);
 201                         free(q);
 202                         break;
 203
 204                 case 'v':
 205                         /* display version */
 206                         verbose++;
 207                         msglog("version 2.22");
 208                         break;
 209
 210                 default:
 211                         goto usage;
 212                 }
 213         }
 214         argc -= optind;
 215         argv += optind;
 216
 217         if (tracename == 0 && argc >= 1) {
 218                 tracename = *argv++;
 219                 argc--;
 220         }
 221         if (tracename != 0 && tracename[0] == '\0')
 222                 goto usage;
 223         if (argc != 0) {
 224 usage:
 225                 logbad(0, "usage: routed [-sqdghmpAtv] [-T tracefile]"
 226                        " [-F net[,metric]] [-P parms]");
 227         }
 228         if (geteuid() != 0) {
 229                 if (verbose)
 230                         exit(0);
 231                 logbad(0, "requires UID 0");
 232         }
 233
 234         mib[0] = CTL_NET;
 235         mib[1] = PF_INET;
 236         mib[2] = IPPROTO_IP;
 237         mib[3] = IPCTL_FORWARDING;
 238         len = sizeof(ipforwarding);
 239         if (sysctl(mib, 4, &ipforwarding, &len, 0, 0) < 0)
 240                 LOGERR("sysctl(IPCTL_FORWARDING)");
 241
 242         if (!ipforwarding) {
 243                 if (supplier)
 244                         msglog("-s incompatible with ipforwarding=0");
 245                 if (default_gateway) {
 246                         msglog("-g incompatible with ipforwarding=0");
 247                         default_gateway = 0;
 248                 }
 249                 supplier = 0;
 250                 supplier_set = 1;
 251         }
 252         if (default_gateway) {
 253                 if (supplier_set && !supplier) {
 254                         msglog("-g and -q incompatible");
 255                 } else {
 256                         supplier = 1;
 257                         supplier_set = 1;
 258                 }
 259         }
 260
 261
 262         signal(SIGALRM, sigalrm);
 263         if (!background)
 264                 signal(SIGHUP, sigterm);    /* SIGHUP fatal during debugging */
 265         signal(SIGTERM, sigterm);
 266         signal(SIGINT, sigterm);
 267         signal(SIGUSR1, sigtrace_on);
 268         signal(SIGUSR2, sigtrace_off);
 269
 270         /* get into the background */
 271         if (background && daemon(0, 1) < 0)
 272                 BADERR(0,"daemon()");
 273
 274         mypid = getpid();
 275         srandom((int)(clk.tv_sec ^ clk.tv_usec ^ mypid));
 276
 277         /* prepare socket connected to the kernel.
 278          */
 279         rt_sock = socket(AF_ROUTE, SOCK_RAW, 0);
 280         if (rt_sock < 0)
 281                 BADERR(1,"rt_sock = socket()");
 282         if (fcntl(rt_sock, F_SETFL, O_NONBLOCK) == -1)
 283                 logbad(1, "fcntl(rt_sock) O_NONBLOCK: %s", strerror(errno));
 284         off = 0;
 285         if (setsockopt(rt_sock, SOL_SOCKET,SO_USELOOPBACK,
 286                        &off,sizeof(off)) < 0)
 287                 LOGERR("setsockopt(SO_USELOOPBACK,0)");
 288
 289         fix_select();
 290
 291
 292         if (tracename != 0) {
 293                 strncpy(inittracename, tracename, sizeof(inittracename)-1);
 294                 set_tracefile(inittracename, "%s", -1);
 295         } else {
 296                 tracelevel_msg("%s", -1);   /* turn on tracing to stdio */
 297         }
 298
 299         bufinit();
 300
 301         /* initialize radix tree */
 302         rtinit();
 303
 304         /* Pick a random part of the second for our output to minimize
 305          * collisions.
 306          *
 307          * Start broadcasting after hearing from other routers, and
 308          * at a random time so a bunch of systems do not get synchronized
 309          * after a power failure.
 310          */
 311         intvl_random(&next_bcast, EPOCH+MIN_WAITTIME, EPOCH+SUPPLY_INTERVAL);
 312         age_timer.tv_usec = next_bcast.tv_usec;
 313         age_timer.tv_sec = EPOCH+MIN_WAITTIME;
 314         rdisc_timer = next_bcast;
 315         ifinit_timer.tv_usec = next_bcast.tv_usec;
 316
 317         /* Collect an initial view of the world by checking the interface
 318          * configuration and the kludge file.
 319          */
 320         gwkludge();
 321         ifinit();
 322
 323         /* Ask for routes */
 324         rip_query();
 325         rdisc_sol();
 326
 327         /* Now turn off stdio if not tracing */
 328         if (new_tracelevel == 0)
 329                 trace_close(background);
 330
 331         /* Loop forever, listening and broadcasting.
 332          */
 333         for (;;) {
 334                 prev_clk = clk;
 335                 gettimeofday(&clk, 0);
 336                 if (prev_clk.tv_sec == clk.tv_sec
 337                     && prev_clk.tv_usec == clk.tv_usec+usec_fudge) {
 338                         /* Much of `routed` depends on time always advancing.
 339                          * On systems that do not guarantee that gettimeofday()
 340                          * produces unique timestamps even if called within
 341                          * a single tick, use trickery like that in classic
 342                          * BSD kernels.
 343                          */
 344                         clk.tv_usec += ++usec_fudge;
 345
 346                 } else {
 347                         usec_fudge = 0;
 348
 349                         timevalsub(&t2, &clk, &prev_clk);
 350                         if (t2.tv_sec < 0
 351                             || t2.tv_sec > wtime.tv_sec + 5) {
 352                                 /* Deal with time changes before other
 353                                  * housekeeping to keep everything straight.
 354                                  */
 355                                 dt = t2.tv_sec;
 356                                 if (dt > 0)
 357                                         dt -= wtime.tv_sec;
 358                                 trace_act("time changed by %d sec", (int)dt);
 359                                 epoch.tv_sec += dt;
 360                         }
 361                 }
 362                 timevalsub(&now, &clk, &epoch);
 363                 now_stale = now.tv_sec - STALE_TIME;
 364                 now_expire = now.tv_sec - EXPIRE_TIME;
 365                 now_garbage = now.tv_sec - GARBAGE_TIME;
 366
 367                 /* deal with signals that should affect tracing */
 368                 set_tracelevel();
 369
 370                 if (stopint != 0) {
 371                         rip_bcast(0);
 372                         rdisc_adv();
 373                         trace_off("exiting with signal %d", stopint);
 374                         exit(stopint | 128);
 375                 }
 376
 377                 /* look for new or dead interfaces */
 378                 timevalsub(&wtime, &ifinit_timer, &now);
 379                 if (wtime.tv_sec <= 0) {
 380                         wtime.tv_sec = 0;
 381                         ifinit();
 382                         rip_query();
 383                         continue;
 384                 }
 385
 386                 /* Check the kernel table occassionally for mysteriously
 387                  * evaporated routes
 388                  */
 389                 timevalsub(&t2, &flush_kern_timer, &now);
 390                 if (t2.tv_sec <= 0) {
 391                         flush_kern();
 392                         flush_kern_timer.tv_sec = (now.tv_sec
 393                                                    + CHECK_QUIET_INTERVAL);
 394                         continue;
 395                 }
 396                 if (timercmp(&t2, &wtime, <))
 397                         wtime = t2;
 398
 399                 /* If it is time, then broadcast our routes.
 400                  */
 401                 if (supplier || advertise_mhome) {
 402                         timevalsub(&t2, &next_bcast, &now);
 403                         if (t2.tv_sec <= 0) {
 404                                 /* Synchronize the aging and broadcast
 405                                  * timers to minimize awakenings
 406                                  */
 407                                 age(0);
 408
 409                                 rip_bcast(0);
 410
 411                                 /* It is desirable to send routing updates
 412                                  * regularly.  So schedule the next update
 413                                  * 30 seconds after the previous one was
 414                                  * scheduled, instead of 30 seconds after
 415                                  * the previous update was finished.
 416                                  * Even if we just started after discovering
 417                                  * a 2nd interface or were otherwise delayed,
 418                                  * pick a 30-second aniversary of the
 419                                  * original broadcast time.
 420                                  */
 421                                 n = 1 + (0-t2.tv_sec)/SUPPLY_INTERVAL;
 422                                 next_bcast.tv_sec += n*SUPPLY_INTERVAL;
 423
 424                                 continue;
 425                         }
 426
 427                         if (timercmp(&t2, &wtime, <))
 428                                 wtime = t2;
 429                 }
 430
 431                 /* If we need a flash update, either do it now or
 432                  * set the delay to end when it is time.
 433                  *
 434                  * If we are within MIN_WAITTIME seconds of a full update,
 435                  * do not bother.
 436                  */
 437                 if (need_flash
 438                     && supplier
 439                     && no_flash.tv_sec+MIN_WAITTIME < next_bcast.tv_sec) {
 440                         /* accurate to the millisecond */
 441                         if (!timercmp(&no_flash, &now, >))
 442                                 rip_bcast(1);
 443                         timevalsub(&t2, &no_flash, &now);
 444                         if (timercmp(&t2, &wtime, <))
 445                                 wtime = t2;
 446                 }
 447
 448                 /* trigger the main aging timer.
 449                  */
 450                 timevalsub(&t2, &age_timer, &now);
 451                 if (t2.tv_sec <= 0) {
 452                         age(0);
 453                         continue;
 454                 }
 455                 if (timercmp(&t2, &wtime, <))
 456                         wtime = t2;
 457
 458                 /* update the kernel routing table
 459                  */
 460                 timevalsub(&t2, &need_kern, &now);
 461                 if (t2.tv_sec <= 0) {
 462                         age(0);
 463                         continue;
 464                 }
 465                 if (timercmp(&t2, &wtime, <))
 466                         wtime = t2;
 467
 468                 /* take care of router discovery,
 469                  * but do it in the correct the millisecond
 470                  */
 471                 if (!timercmp(&rdisc_timer, &now, >)) {
 472                         rdisc_age(0);
 473                         continue;
 474                 }
 475                 timevalsub(&t2, &rdisc_timer, &now);
 476                 if (timercmp(&t2, &wtime, <))
 477                         wtime = t2;
 478
 479
 480                 /* wait for input or a timer to expire.
 481                  */
 482                 trace_flush();
 483                 ibits = fdbits;
 484                 n = select(sock_max, &ibits, 0, 0, &wtime);
 485                 if (n <= 0) {
 486                         if (n < 0 && errno != EINTR && errno != EAGAIN)
 487                                 BADERR(1,"select");
 488                         continue;
 489                 }
 490
 491                 if (FD_ISSET(rt_sock, &ibits)) {
 492                         read_rt();
 493                         n--;
 494                 }
 495                 if (rdisc_sock >= 0 && FD_ISSET(rdisc_sock, &ibits)) {
 496                         read_d();
 497                         n--;
 498                 }
 499                 if (rip_sock >= 0 && FD_ISSET(rip_sock, &ibits)) {
 500                         read_rip(rip_sock, 0);
 501                         n--;
 502                 }
 503
 504                 for (ifp = ifnet; n > 0 && 0 != ifp; ifp = ifp->int_next) {
 505                         if (ifp->int_rip_sock >= 0
 506                             && FD_ISSET(ifp->int_rip_sock, &ibits)) {
 507                                 read_rip(ifp->int_rip_sock, ifp);
 508                                 n--;
 509                         }
 510                 }
 511         }
 512 }
 513
 514
 515 /* ARGSUSED */
 516 void
 517 sigalrm(__unused int s)
 518 {
 519         /* Historically, SIGALRM would cause the daemon to check for
 520          * new and broken interfaces.
 521          */
 522         ifinit_timer.tv_sec = now.tv_sec;
 523         trace_act("SIGALRM");
 524 }
 525
 526
 527 /* watch for fatal signals */
 528 void
 529 sigterm(int sig)
 530 {
 531         stopint = sig;
 532         signal(sig, SIG_DFL);   /* catch it only once */
 533 }
 534
 535
 536 void
 537 fix_select(void)
 538 {
 539         struct interface *ifp;
 540
 541
 542         FD_ZERO(&fdbits);
 543         sock_max = 0;
 544
 545         FD_SET(rt_sock, &fdbits);
 546         if (sock_max <= rt_sock)
 547                 sock_max = rt_sock+1;
 548         if (rip_sock >= 0) {
 549                 FD_SET(rip_sock, &fdbits);
 550                 if (sock_max <= rip_sock)
 551                         sock_max = rip_sock+1;
 552         }
 553         for (ifp = ifnet; NULL != ifp; ifp = ifp->int_next) {
 554                 if (ifp->int_rip_sock >= 0) {
 555                         FD_SET(ifp->int_rip_sock, &fdbits);
 556                         if (sock_max <= ifp->int_rip_sock)
 557                                 sock_max = ifp->int_rip_sock+1;
 558                 }
 559         }
 560         if (rdisc_sock >= 0) {
 561                 FD_SET(rdisc_sock, &fdbits);
 562                 if (sock_max <= rdisc_sock)
 563                         sock_max = rdisc_sock+1;
 564         }
 565 }
 566
 567
 568 void
 569 fix_sock(int sock,
 570          const char *name)
 571 {
 572         int on;
 573 #define MIN_SOCKBUF (4*1024)
 574         static int rbuf;
 575
 576         if (fcntl(sock, F_SETFL, O_NONBLOCK) == -1)
 577                 logbad(1, "fcntl(%s) O_NONBLOCK: %s",
 578                        name, strerror(errno));
 579         on = 1;
 580         if (setsockopt(sock, SOL_SOCKET,SO_BROADCAST, &on,sizeof(on)) < 0)
 581                 msglog("setsockopt(%s,SO_BROADCAST): %s",
 582                        name, strerror(errno));
 583 #ifdef USE_PASSIFNAME
 584         on = 1;
 585         if (setsockopt(sock, SOL_SOCKET, SO_PASSIFNAME, &on,sizeof(on)) < 0)
 586                 msglog("setsockopt(%s,SO_PASSIFNAME): %s",
 587                        name, strerror(errno));
 588 #endif
 589
 590         if (rbuf >= MIN_SOCKBUF) {
 591                 if (setsockopt(sock, SOL_SOCKET, SO_RCVBUF,
 592                                &rbuf, sizeof(rbuf)) < 0)
 593                         msglog("setsockopt(%s,SO_RCVBUF=%d): %s",
 594                                name, rbuf, strerror(errno));
 595         } else {
 596                 for (rbuf = 60*1024; ; rbuf -= 4096) {
 597                         if (setsockopt(sock, SOL_SOCKET, SO_RCVBUF,
 598                                        &rbuf, sizeof(rbuf)) == 0) {
 599                                 trace_act("RCVBUF=%d", rbuf);
 600                                 break;
 601                         }
 602                         if (rbuf < MIN_SOCKBUF) {
 603                                 msglog("setsockopt(%s,SO_RCVBUF = %d): %s",
 604                                        name, rbuf, strerror(errno));
 605                                 break;
 606                         }
 607                 }
 608         }
 609 }
 610
 611
 612 /* get a rip socket
 613  */
 614 static int                              /* <0 or file descriptor */
 615 get_rip_sock(naddr addr,
 616              int serious)               /* 1=failure to bind is serious */
 617 {
 618         struct sockaddr_in in;
 619         unsigned char ttl;
 620         int s;
 621
 622
 623         if ((s = socket(AF_INET, SOCK_DGRAM, 0)) < 0)
 624                 BADERR(1,"rip_sock = socket()");
 625
 626         memset(&in, 0, sizeof(in));
 627 #ifdef _HAVE_SIN_LEN
 628         in.sin_len = sizeof(in);
 629 #endif
 630         in.sin_family = AF_INET;
 631         in.sin_port = htons(RIP_PORT);
 632         in.sin_addr.s_addr = addr;
 633         if (bind(s, (struct sockaddr *)&in, sizeof(in)) < 0) {
 634                 if (serious)
 635                         BADERR(errno != EADDRINUSE, "bind(rip_sock)");
 636                 return -1;
 637         }
 638         fix_sock(s,"rip_sock");
 639
 640         ttl = 1;
 641         if (setsockopt(s, IPPROTO_IP, IP_MULTICAST_TTL,
 642                        &ttl, sizeof(ttl)) < 0)
 643                 DBGERR(1,"rip_sock setsockopt(IP_MULTICAST_TTL)");
 644
 645         return s;
 646 }
 647
 648
 649 /* turn off main RIP socket */
 650 void
 651 rip_off(void)
 652 {
 653         struct interface *ifp;
 654         naddr addr;
 655
 656
 657         if (rip_sock >= 0 && !mhome) {
 658                 trace_act("turn off RIP");
 659
 660                 close(rip_sock);
 661                 rip_sock = -1;
 662
 663                 /* get non-broadcast sockets to listen to queries.
 664                  */
 665                 for (ifp = ifnet; ifp != NULL; ifp = ifp->int_next) {
 666                         if (ifp->int_state & IS_REMOTE)
 667                                 continue;
 668                         if (ifp->int_rip_sock < 0) {
 669                                 addr = ((ifp->int_if_flags & IFF_POINTOPOINT)
 670                                         ? ifp->int_dstaddr
 671                                         : ifp->int_addr);
 672                                 ifp->int_rip_sock = get_rip_sock(addr, 0);
 673                         }
 674                 }
 675
 676                 fix_select();
 677
 678                 age(0);
 679         }
 680 }
 681
 682
 683 /* turn on RIP multicast input via an interface
 684  */
 685 static void
 686 rip_mcast_on(struct interface *ifp)
 687 {
 688         struct ip_mreq m;
 689
 690         if (!IS_RIP_IN_OFF(ifp->int_state)
 691             && (ifp->int_if_flags & IFF_MULTICAST)
 692 #ifdef MCAST_PPP_BUG
 693             && !(ifp->int_if_flags & IFF_POINTOPOINT)
 694 #endif
 695             && !(ifp->int_state & IS_ALIAS)) {
 696                 m.imr_multiaddr.s_addr = htonl(INADDR_RIP_GROUP);
 697                 m.imr_interface.s_addr = ((ifp->int_if_flags & IFF_POINTOPOINT)
 698                                           ? ifp->int_dstaddr
 699                                           : ifp->int_addr);
 700                 if (setsockopt(rip_sock,IPPROTO_IP, IP_ADD_MEMBERSHIP,
 701                                &m, sizeof(m)) < 0)
 702                         LOGERR("setsockopt(IP_ADD_MEMBERSHIP RIP)");
 703         }
 704 }
 705
 706
 707 /* Prepare socket used for RIP.
 708  */
 709 void
 710 rip_on(struct interface *ifp)
 711 {
 712         /* If the main RIP socket is already alive, only start receiving
 713          * multicasts for this interface.
 714          */
 715         if (rip_sock >= 0) {
 716                 if (ifp != NULL)
 717                         rip_mcast_on(ifp);
 718                 return;
 719         }
 720
 721         /* If the main RIP socket is off and it makes sense to turn it on,
 722          * then turn it on for all of the interfaces.
 723          * It makes sense if either router discovery is off, or if
 724          * router discover is on and at most one interface is doing RIP.
 725          */
 726         if (rip_interfaces > 0 && (!rdisc_ok || rip_interfaces > 1)) {
 727                 trace_act("turn on RIP");
 728
 729                 /* Close all of the query sockets so that we can open
 730                  * the main socket.  SO_REUSEPORT is not a solution,
 731                  * since that would let two daemons bind to the broadcast
 732                  * socket.
 733                  */
 734                 for (ifp = ifnet; ifp != NULL; ifp = ifp->int_next) {
 735                         if (ifp->int_rip_sock >= 0) {
 736                                 close(ifp->int_rip_sock);
 737                                 ifp->int_rip_sock = -1;
 738                         }
 739                 }
 740
 741                 rip_sock = get_rip_sock(INADDR_ANY, 1);
 742                 rip_sock_mcast = NULL;
 743
 744                 /* Do not advertise anything until we have heard something
 745                  */
 746                 if (next_bcast.tv_sec < now.tv_sec+MIN_WAITTIME)
 747                         next_bcast.tv_sec = now.tv_sec+MIN_WAITTIME;
 748
 749                 for (ifp = ifnet; ifp != NULL; ifp = ifp->int_next) {
 750                         ifp->int_query_time = NEVER;
 751                         rip_mcast_on(ifp);
 752                 }
 753                 ifinit_timer.tv_sec = now.tv_sec;
 754
 755         } else if (ifp != NULL
 756                    && !(ifp->int_state & IS_REMOTE)
 757                    && ifp->int_rip_sock < 0) {
 758                 /* RIP is off, so ensure there are sockets on which
 759                  * to listen for queries.
 760                  */
 761                 ifp->int_rip_sock = get_rip_sock(ifp->int_addr, 0);
 762         }
 763
 764         fix_select();
 765 }
 766
 767
 768 /* die if malloc(3) fails
 769  */
 770 void *
 771 rtmalloc(size_t size,
 772          const char *msg)
 773 {
 774         void *p = malloc(size);
 775         if (p == NULL)
 776                 logbad(1,"malloc(%lu) failed in %s", (u_long)size, msg);
 777         return p;
 778 }
 779
 780
 781 /* get a random instant in an interval
 782  */
 783 void
 784 intvl_random(struct timeval *tp,        /* put value here */
 785              u_long lo,                 /* value is after this second */
 786              u_long hi)                 /* and before this */
 787 {
 788         tp->tv_sec = (time_t)(hi == lo
 789                               ? lo
 790                               : (lo + random() % ((hi - lo))));
 791         tp->tv_usec = random() % 1000000;
 792 }
 793
 794
 795 void
 796 timevaladd(struct timeval *t1,
 797            struct timeval *t2)
 798 {
 799
 800         t1->tv_sec += t2->tv_sec;
 801         if ((t1->tv_usec += t2->tv_usec) >= 1000000) {
 802                 t1->tv_sec++;
 803                 t1->tv_usec -= 1000000;
 804         }
 805 }
 806
 807
 808 /* t1 = t2 - t3
 809  */
 810 static void
 811 timevalsub(struct timeval *t1,
 812            struct timeval *t2,
 813            struct timeval *t3)
 814 {
 815         t1->tv_sec = t2->tv_sec - t3->tv_sec;
 816         if ((t1->tv_usec = t2->tv_usec - t3->tv_usec) < 0) {
 817                 t1->tv_sec--;
 818                 t1->tv_usec += 1000000;
 819         }
 820 }
 821
 822
 823 /* put a message into the system log
 824  */
 825 void
 826 msglog(const char *p, ...)
 827 {
 828         va_list args;
 829
 830         trace_flush();
 831
 832         va_start(args, p);
 833         vsyslog(LOG_ERR, p, args);
 834
 835         if (ftrace != 0) {
 836                 if (ftrace == stdout)
 837                         fputs("routed: ", ftrace);
 838                 vfprintf(ftrace, p, args);
 839                 fputc('\n', ftrace);
 840         }
 841 }
 842
 843
 844 /* Put a message about a bad system into the system log if
 845  * we have not complained about it recently.
 846  *
 847  * It is desirable to complain about all bad systems, but not too often.
 848  * In the worst case, it is not practical to keep track of all bad systems.
 849  * For example, there can be many systems with the wrong password.
 850  */
 851 void
 852 msglim(struct msg_limit *lim, naddr addr, const char *p, ...)
 853 {
 854         va_list args;
 855         int i;
 856         struct msg_sub *ms1, *ms;
 857         const char *p1;
 858
 859         va_start(args, p);
 860
 861         /* look for the oldest slot in the table
 862          * or the slot for the bad router.
 863          */
 864         ms = ms1 = lim->subs;
 865         for (i = MSG_SUBJECT_N; ; i--, ms1++) {
 866                 if (i == 0) {
 867                         /* Reuse a slot at most once every 10 minutes.
 868                          */
 869                         if (lim->reuse > now.tv_sec) {
 870                                 ms = NULL;
 871                         } else {
 872                                 ms = ms1;
 873                                 lim->reuse = now.tv_sec + 10*60;
 874                         }
 875                         break;
 876                 }
 877                 if (ms->addr == addr) {
 878                         /* Repeat a complaint about a given system at
 879                          * most once an hour.
 880                          */
 881                         if (ms->until > now.tv_sec)
 882                                 ms = NULL;
 883                         break;
 884                 }
 885                 if (ms->until < ms1->until)
 886                         ms = ms1;
 887         }
 888         if (ms != NULL) {
 889                 ms->addr = addr;
 890                 ms->until = now.tv_sec + 60*60; /* 60 minutes */
 891
 892                 trace_flush();
 893                 for (p1 = p; *p1 == ' '; p1++)
 894                         continue;
 895                 vsyslog(LOG_ERR, p1, args);
 896         }
 897
 898         /* always display the message if tracing */
 899         if (ftrace != 0) {
 900                 vfprintf(ftrace, p, args);
 901                 fputc('\n', ftrace);
 902         }
 903 }
 904
 905
 906 void
 907 logbad(int dump, const char *p, ...)
 908 {
 909         va_list args;
 910
 911         trace_flush();
 912
 913         va_start(args, p);
 914         vsyslog(LOG_ERR, p, args);
 915
 916         fputs("routed: ", stderr);
 917         vfprintf(stderr, p, args);
 918         fputs("; giving up\n",stderr);
 919         fflush(stderr);
 920
 921         if (dump)
 922                 abort();
 923         exit(1);
 924 }